'Star Wars' Desert Planet Tatooine May be Common in the Universe

Luke Skywalker's home planet, Tatooine, may actually be common in the universe. Scientists have found that rocky, desert planets with twin suns may be widespread.

"Tatooine sunsets may be common after all," said Ben Bromley, one of the researchers, in a news release. "Our main result is that outside a small region near a binary star [either rocky or gas-giant] planet formation can proceed in much the same way as around a single star. In our scenario, planets are as prevalent around binaries as around single stars."

In this latest study, the researchers used mathematical formulas to see how planetesimals can orbit binary stars. These calculations revealed that the orbit around two stars can be just as smooth as around one.

"For over a decade, astrophysicists believed that planets like Earth could not form around most binary stars, at least not close enough to support life," said S. J. Kenyon, one of the researchers. "The problem is that planetesimals need to merge gently together to grow. Around a single star, planetesimals tend to follow circular paths-concentric rings that do not cross. If planetesimals do approach each other, they can merge together gently."

The researchers didn't conduct their simulations to the point of planet formation. However, they did show that planetesimals could survive without collisions for tens of thousands of years in concentric, oval-shaped orbits around binary stars.

"We are saying you can set the stage to make these things," said Bromley. "It is just as easy to make an Earthlike planet around a binary star as it is around a single star like our sun. So we think that Tatooines may be common in the universe."

The findings reveal a bit more about the universe and show that a planet with twin suns may be possible. So far, Kepler has found seven planets orbiting within or near the habitable zone around binary stars, but all of them are giant, gaseous planets.